In the normal, homeostatic situation, the immune system regulates its own activity with exquisite sensitivity. However, a disordered immune response initiates and perpetuates a large number of serious pathological conditions, ranging from lymphocytic neoplasms to autoimmune disorders. In contrast to the efficient, clone-specific manner in which the normal immune system regulates itself, standard methods of treating these immunopathological states have employed immunosuppressive reagents to ablate the immune response altogether. Whereas this approach has been of tremendous benefit in particular instances of autoimmunes disease or graft rejection, its applicability is limited by the very real dangers of crippling an immune system required for the maintenance of the integrity of the individual. More recently, based upon an evolving understanding of basic immunology, investigators using a wide variety of approaches have developed model systems, and even patient applications, that utilize reagents and/or methodologies that successfully result in modulation of the immune response in an antigen-specific and/or clone-specific fashion. In situations ranging from the induction of antigen-specific T cell tolerance in vitro to the generation of specific anti-tumor T cell responses in vivo, highly selective approaches are being developed. Such approaches are quite attractive with respect to the development of new treatments of diseases of the immune system, since they have the potential of leaving responses to most independent antigens unperturbed. The should attract participants and an audience representing a wide range of interests and expertise. Its purpose is to bring together individuals whose work bears on the topic of antigen- and clone specific modulation of immune function, with an emphasis on the diversity of the experimental approaches and systems used. It is expected that the interaction between basic scientists, clinical researches and clinicians will promote new approaches to the directed therapy of disorders whose pathogenesis includes inappropriate immune responses.